Field of the Invention
This invention relates generally to steerable toy vehicles driven by a battery-powered d-c motor, and in particular to a toy of this type which is remotely controlled by means of a handset linked through a flexible pneumatic line to the motor control switch and the steering mechanism of the vehicle by a master-slave pneumatic system whereby the player holding the handset is able to control the direction of travel as well as to steer the vehicle.
It is known to control a d-c motor driven vehicle through a hand-held unit containing batteries and switches which are connected by a flexible tether cable to the vehicle. This arrangement has practical drawbacks; for the control unit which houses the batteries and switches is fairly heavy. Consequently, a child playing with the unit may drop it, with possible switch breakage or damage to the batteries.
In order to avoid the need to house electrical components in the control unit, the Masuda U.S. Pat. No. 3,671,694, discloses a light-weight control unit for a battery-powered toy vehicle provided with a manually-operated master bellows. The master bellows is pneumatically coupled through a flexible pipe to a slave bellows in the vehicle, such that manual compression of the master bellows by the player produces a flow of pressurized air causing expansion of the slave bellows, the reverse action taking place when the master is expanded.
In the Masuda arrangement, the slave bellows is operatively coupled to both the steering mechanism of the vehicle and to the motor-control switch which in one position causes the motor to drive the vehicle in the forward direction, and in another to drive the vehicle in reverse. This bellows is provided with a stop to limit its expansion to a predetermined range, control of the motor switch being effected when the bellows is operated within this range. Steering is effected only when the bellows is operated beyond this predetermined range.
In the Okuma U.S. Pat. No. 3,545,125, steering and motor control of a vehicle is carried out by a control unit having a master bellows therein coupled by a flexible pipe both to a motor-control slave bellows in the vehicle and a steering-control slave bellows therein, a valve acting to regulate the distribution of air between the two slave bellows.
In both the Masuda and Okuma patents, the player holding the control unit effects steering or motor control by applying pressure to a manual bellows actuator, this manual operation in dynamic terms being unrelated to the direction of steering or travel. Lacking, therefore, is the play satisfaction one gains by a rudder-like steering operation in which the direction of vehicle movement depends on the direction of rudder movement so that the child is then in the role of a pilot or driver, and by a gear shift operation which determines whether the vehicle travels in forward or reverse.
Also of background interest are the patents to Jackson, Pat. No. 2,638,712; Puckett, Pat. No. 2,795,668; Bunting, Pat. No. 2,668,821 and Hauge, Pat. No. 2,940,217.